2450 (78mm x 100mm) engine build

[Eddie010]

Ok,

You guys asked me to put a topic here for the build of my new engine.
This is the plan, been collecting parts. Hope I have enough spare time to do this this summer.
76.4 DPR Counterweighted welded crank with 55mm taps (66mm Rod taps)
ADV performance 133mm H beam rods (22mm piston pen)
Deutz cilinders 100mm
Type 4 100mm JE pistons
Webcam 86b 108 degr lobe center
Thortsten Pieper type 1 cam followers(56gr)
Thortsten Pieper tapered push rods.
NOS 45 Dellorto carbs.
Will be using my current heads 42x36 (stainless steel 8mm stem valves).
30mm ADV oil pump.
Will try to update the built here.

Wanted to built a 4 inch engine (101.6mm) , but costs of machining the deutz cilinders and 4 inch pistons was a little bit to steep.
When i came across the 100mm JE pistons for cheap on e-bay.. the choice was made easy for me.

Oh I live in europe (The Netherlands) It will be in a Cal Look car...
already have a 2.0 type 4 engine (125 HP) own built with upright cooling in my car for 6 years.
Want a bit more HP
But Cal Look guys don t like type 4 engines... But I don t care.

[Eddie010]

Oh try to do most of the work myself.
Already prepared a CJ case for type 1 lifters.
Modified the rockers for 10 mm swivel feet adjusters.

[wreck]

Looks good Eddie . the cost of boring my Deutz cylinders to 103mm was high but understandable with the time taken to the job correctly , they work out affordable in the long run because you can get them rebored for over size in years to come .

[Clatter]

SwEEt Build!

Looking forward to seeing this coming together..

[Eddie010]

Ok the parts I gathered so far.

Deutz test cylinder on spec of a 94mm
The ProsSeal came with the pistons
H beam for 66mm tap (55mm/133mm lenght) on top. under H-beam for the 71mm tap (50mm/131mm lenght).
Bushes to adjust the type 4 case for type 1 cam followers
10mm Swivelfeet
The piston pen 22mm fits the H-beam
Webcam cam








Regards Edgar

[patto]

Looking forward to this build, some very nice parts going in to it

[Eddie010]

Some more parts.
Try to keep the engine parts light.




I think i got all the parts now.

[Eddie010]

I have a question, is the type 1 oil pressure relief spring the same as a type 4 oil pressure spring... because I read that you have to replace them on rebuild of your engine... but can not find a type 4 spring.

Thanks in advance.
Edgar

[wreck]

I'm using the old spring that was in the second hand case with no issues.There is information on what the spring length at a certain compression should be if you do a search on google .

[Clatter]

Couple of thoughts...

Even without the titanium retainers, the 86b is supposed to be easily controlled by a set of regular dual springs.
Those 650s will be quite overkill for your application.
Normal 'duals' with an 86b will control steel pushrods and heavy steel retainers easily even..
Light valvetrain guys are supposedly running an 86b on singles.
What with type 1 lifters and all, I'd be re-thinking those 650s.
Why waste power needlessly compressing heavy springs?


One other way to save weight on the valvetrain is to maybe source a set of the 1.7 rockers,
So you can use the smaller adjusters.
Now that CB sells the adjusters, they need not cost a ton.
Can you weigh one of those new big swivel feet?
Wondering how much they weigh compared to the old standard/smaller ones..
Might not be that much; I can weigh a smaller one here for you if you don't have one.

I really dig your build.
been following it on cal-look.no for years,
And am always stoked to see your work.

This new combo will make for a lot of fun.

[Clatter]

I never heard that you had to replace plunger relief springs before.

Just make sure they match the specs given by the scriptures on the Bentley..

[Eddie010]

Hm rethink the 650s, ok I will do.
But I choose them because the 86B according to webcam needs dual springs, and hearing a lot off positive
comments on the 650s. so that was the reason why I bought them.
But will look on the internet if it is maybe an overkill. Thanks for that inside.

As a matter of fact i never weight the swivel feet, I weight all the other stuff. So as soon as I am in my garage I will weigh them.

On the pressure spring, they tend to wear after years of use, which will result in to little oil pressure at idle.
But the problem is I can not find what the correct spec are for that spring.. I have searched but can not find it..
So if you guys can provide me with the correct info, would be highly appreciated.

Thanks for the kind words Clatter.

[Eddie010]

Ooh I don t have a Bentley manual, but an old garage manual, I will have a look if I can find some info there too.

[wreck]

Now my engine has a few thousand kms on it I'm starting to shim up the relief spring to increase the high level pressure , at the moment with 15w50 oil at 90C it's regulated at approx 300kpa( 43psi) which is the standard pressure. I'm planing on just increasing the spring pressure up to give 450 kpa(65psi) which from my research should be ok for the short times it see's 7000 rpm .

[raygreenwood]

The specs for the oil pressure relief valve spring for type 4 engines are:


When loaded to 39mm (1.54") = 6.8 to 8.8 kg (15 to 19 lbs.) For the oil pressure relief valve near the oil pump.

For the oil pressure control valve under #1 cylinder:
When loaded to 26mm (1.02") = 1.7 to 2.0 kg (3.7 to 4.4 lbs)

Ray